When the dog is lead on a leash, the steps, the movement of the shoulders of the dog, and the periodic movement of the person holding the leash result in micro-tuggings, which put a load on the joints and can make the healing of injuries difficult. These effects are collectively called HAVS, that is: Hand-Arm Vibration Syndrome. The elastic chest strap is designed to eliminate the adverse effects of the micro-tuggings generated when leading the dog on a leash, while following every move of the dog and the leash.
In the field of technical and structural design, it is essential to quantify, to determine the specifics, the exact values of the different mechanical properties.
The task of the dog harness and the leash is to implement a connection between two bodies of different weights, speeds and speed directions with the lowest possible maximum force. The ratio of the two bodies, the human and the dog, covers a wide range, and therefore, the elastic element of the dog harness is produced in different sizes, with different mechanical properties. In the case of a constantly tight leash, a “static” pulling force acts, which is favourable in terms of peak force.
During the movement of the human and the dog, as a result of the steps and the swinging of the arm, a continuous periodic-dynamic excitation occurs, the load causes a so-called tugging force which can have an adverse effect on the joints, depending on its strength. The elastic dog harness of the present invention is specifically directed to dampening this effect.
In the case of a loose leash, tugging occurs at the moment of the straightening of the leash as a result of a jump in speed. In theory, in the case of a perfectly rigid structure, the “force acting” upon tugging “as a result of infinitely high acceleration” is “infinitely high.” In reality, however, due to the elasticity of the connection points of the leash and the harness, the duration of tugging increases, which can be significant in spite of a reduction in the peak force, depending on the speed and weight conditions, and the elasticity of the connection. In addition, the tugging force acts unexpectedly, shockingly, catching both the human and the dog unprepared. The high force and shock resulting from tugging can be reduced by incorporating elastic elements of the planned design into the dog harness. Tugging occurs when there is a big difference between the acceleration of the two bodies. The design of elastic elements has to take into consideration the load, stress acting on the material, and on the participants. Both humans and dogs need time for their muscles to adapt to the load changes safely.
Diseases associated with vibration-tugging load on the human hand and arm, such as the Raynaud's Syndrome, the Carpal Tunnel Syndrome, and diseases involving the inflammation of the tendons, have provided a basis for examining how similar loads act on the body of the dog and the human holding the leash while leading the dog on a leash, and how these loads could be reduced by a dog harness equipped with an elastic chest strap of sized stretching. Research and development can result in unexpected effects in terms of the location, length and fixing of the elastic elements. In the prior art, there has been no research into the forces acting during the street use of dog harnesses, and into the reduction of the peak forces.
The micro-tuggings can be dampened by elastic elements incorporated into the dog harnesses. The importance of pulling or driving horse harnesses known in the prior art has been superseded by the development of technology and motorization, but through the centuries, there was no demand for an elastic design for pulling harnesses. In the case of pulling chest harnesses, it was not desirable to reduce the forces acting on the shoulder joints. In contrast, the market of harnesses developed for dogs is expanding, as it is the ideal solution for leading a dog on a leash.
The dog harnesses found in the prior art are made of leather and/or textile straps, padded on the back part, chest part and belly part of the dog in a fixed, or sometimes in a releasable manner. The purpose of padding is to distribute the pressure over the surface of the body, to stabilize the straps, and to allow the attachment, display of additional equipment (e.g. bags, GPS, light or camera devices) and/or graphic elements, high visibility colours, labels on the padding itself, or on the cover thereof. The straps covering the belly part and the chest bone part (the chest strap and the belly strap) are subjected to increased stress when the dog is lead on a leash, or during training and police work. On dog chest harnesses according to the prior art, these straps are fixed together, they are form-stable, capable of minimal stretching in practice. The straps of the harnesses are made by band weaving, by interlacing warp yarns and weft yarns made from synthetic filaments, such as polyester (PES), polypropylene (PP), and polyamide (PA) fibers. The stretching of these high-tensile strength straps (Ultimate Tensile Force F=700N) on the dog harness under load is practically negligible. Their stretchability, that is, elasticity, is far below that of rubber, silicone or elastomer materials.
It is commonly known that especially the bones of developing young dogs and old dogs need to be spared from strong mechanical impacts. This includes even the load resulting from the daily walk on a leash. The padding of the chest strap and/or the belly strap is only a partial solution for reducing the micro-tugging forces.
Another load, a sudden great tugging force, occurs upon an unexpected jump in speed, at the moment of the straightening of the leash. Such a shock-like load is not sufficiently reduced by the padding materials, or padded straps.
The adverse effects of the load acting when leading the dog on a leash can be reduced in the area of the chest strap.
The chest straps of dog harnesses preferably consist of at least two parts, but there are also undivided, non-adjustable chest straps made of one strap connecting the two sides of the harness and also the two ends of the back strap, in the continuation thereof.
The most common chest strap design for dog harnesses is a Hungarian development from 1997, which is a chest strap running horizontally at the height of the chest bone of the dog, divided into two main parts, adjustable by a hook-and-loop fastener by threading it through a fastener/slide adjuster. It is special in that it uses the hook-and-loop fastener closure used for shoes as well, threaded through a loop adjuster and closing on itself from the opposite side, closing in the direction of the load. Thus, under load, the chest of the dog presses the hook-and-loop fastener components together, and they are prevented from opening by the conditions of use themselves. This dog harness was introduced into regular use, first for Austrian, then for German service dog units, under the name “K9-Powerharness” (DE302009060989). As the name of the device already suggests, it was designed for high stresses occurring especially in the case of service and sports dogs.
The chest strap, attached to the connection point of the back strap and/or the belly strap, in the continuation thereof, on one side of the dog harness, ends in a cut edge, while on the other side, it preferably ends in an oval fastener/slide adjuster, or frame. The chest strap gets in a state ready for use by threading through this fastener/slide adjuster and closing on itself. Thus, in this case, the chest strap is divided into two parts: there is one section on one side of the dog harness, extending from an oval ring-shaped fastener/slide adjuster to the connection point of the belly strap and/or back strap, the so-called chest strap part holding a fastener/slide adjuster, while there is another section on the other side of the dog harness, closing on itself, threaded through the fastener/slide adjuster during use, the so-called adjustable-length chest strap part, or chest strap part crossing the chest bone. This chest strap section extends from the cut edge of the adjustable-length chest strap part, equipped with a hook-and-loop fastener, to the connection point of the adjustable-length chest strap part and the back strap and/or the belly strap. In the prior art, pressure distributors for chest straps, generally made of an elastic material, are attached to the hook-and-loop fastener of the latter, the adjustable-length chest strap part of the chest strap closing on itself, and/or to the chest strap itself.
Utility model file No. U1000003 discloses a pressure distributor incorporating a chest pad made of an elastic material that is not only threaded onto the chest strap of a chest harness, but is also attached to the hook-and-loop fastener thereof. The chest pad makes it much easier for the dog to tolerate lifting, for example by the handle fixed on the harness. In the event of a sudden load in the direction of movement, the chest of the dog is supported by the whole width of the surface of the chest pad, but its stretching is practically minimal, so its load absorbing capacity is low. The chest strap of the dog harness is not of elastic design.
Utility model file No. U1100245, disclosing a so called “I” connecting element of partially elastic design, also describes the padding of the chest strap of the dog harness. This pressure distribution device is mounted on the chest strap in a releasable manner, perpendicularly to it, and it connects the chest strap and the belly strap of the harness, and at the same time, it can be connected to the collar as well. The significance of the device is that, by fixing three points together, the use of the harness becomes safer, for example for service/assault dogs, as it prevents the chest strap of the dog harness from sliding down towards the forelegs of the dog during vigorous movement. However, this pressure distribution device has the disadvantage that it affects only to a minimum extent the distribution of the load on the chest part and the shoulder joints. The device is not suitable for dampening the micro-tuggings generated when leading the dog on a leash. Nevertheless, the significance of the device is indisputable, as the “I” connecting element was the first pressure distribution element including an elastic portion that was mountable on the chest strap of dog chest harnesses in a releasable manner. While the device is attached to the chest strap of the dog harness by means of straps incapable of elastic stretching, at the opposite end, it is connected to the collar by means of a rubber ring of elastic design. However, the limitation of stretching is not implemented in that development. The elastic portion of the pressure distribution device is in direct contact with the body of the dog, and can put an undesirable load on the fur of the dog, if the instructions for use are not followed exactly by the user.
The development and spread of pressure distribution devices mountable on dog chest harnesses among hobby dog owners clearly proves that there is a demand for dampening the forces acting when leading the dog on a leash.
Patent No. US20070034164 A1 discloses an elastic design for dog harnesses. On the chest part of an elastic harness to be used for dogs, an elastic insert is included between the load-bearing, non-elastic straps. The biggest disadvantage of the development is that the elastic elements are not covered, and their stretching is not limited. Therefore, while the elastic portion can be made durable, its fatigue can be avoided only by using an oversized, excessively wide/thick elastic portion in direct contact with the body of the dog. No calculation or design for, or reference to, sizing is included in the patent.
The dog harness of Zimmerman (US 20070044735 A1) has been developed for special use. This development, however, refers only in general to the use of elastic straps, for added comfort. Generally, they allow a form fitting, comfortable design.
The developments listed above are not suitable for the long-term, elastic compensation of the forces acting when leading the dog on a leash. The above solutions are intended for other, specific purposes. The elastic elements are included not as a function of the forces acting between the chest strap and the leash ring, and not for the purpose of dampening them.
All prior art developments also have the disadvantage that the elastic elements are not covered or wrapped. Thereby, the elastic elements are directly exposed to environmental effects, and primarily the harmful UV rays of the sun. Furthermore, in the event of repeated tuggings, the elastic portions are not relieved by a limiting element. The elastic elements are also load-bearing elements, whereby they wear out more frequently. Elastic design is incorporated into the devices as a function arising obviously from elasticity. Therefore, the permanent, deforming stretching of the elastic portion is inevitable, and its breaking can only be avoided by using it only in the lower range of elastic stretching.
The long-term safe use of the stretching elements is of primary importance, and it is possible only if the stretching of the elastic structural elements is limited by a separate structural element.
Another development is Chest harness with an elastic chest strap filed under application No. EP20150000491. In this development, the stretching of the elastic portion is limited by an element limiting the stretching of the elastic portion. The element limiting the stretching of the elastic portion is a bulging part of the chest strap part holding a fastener/adjuster ring, or the chest strap part holding a frame. The limitation of stretching increases the service life of the elastic portion.
A disadvantage of this development is that the elastic portion is looped around the fastener/adjuster ring or frame loosely, and it is not tightened on the ring or frame to prevent it from turning out. The fastener/adjuster ring is only an elongated, oval element, the interior of which is not divided into separate through openings for the chest strap part crossing the chest bone and the chest strap part holding a fastener/adjuster ring. Furthermore, its interior lacks angular connections as it is curved, which has the disadvantage of making it possible for the straps threaded through it to get wrinkled.
The fastener/adjuster ring can turn out as a result of the loads, and this cannot be prevented by the element limiting the stretching of the elastic portion, forming a loose loop, as it is not holding the fastener/adjuster ring tightly. This can lead to the fastener/adjuster ring or frame holding the chest strap turning with its narrower side into the horizontal direction under load and wrinkling the chest strap as a result of prolonged or intensive use. The chest strap can slide down to the legs of the dog even during normal use, as the size of the fastener/adjuster ring allows this. The element limiting the stretching of the elastic portion is a loose loop, which is disadvantageous because it allows the displacement or turning out of the ring. The design of the element limiting the stretching of the elastic portion contains no details or calculations about the size of the forces acting between the leash ring and the chest strap, and the length of the stretch limiting element. Therefore, its design according to this prior art development is haphazard.
A further disadvantage is that the sewing used in this development fixes both the elastic portion and the element limiting the stretching of the elastic portion, which makes it impossible to design the length of the elastic portion, or at least to increase its length to any substantial extent.
The sewing connecting together the elastic portion and the element limiting the stretching thereof is directly beside the fastener/adjuster ring. The stretching of the elastic portion is possible only over the section surrounding the fastener/adjuster ring or frame, up to the sewing running beside the fastener/adjuster ring. Thereby, the load generated when leading the dog on a leash places increased stress on the structure of the elastic portion fixing the fastener/adjuster ring as well. The chest harness with an elastic chest strap does not provide a solution for a significant extension of the stretching part of the elastic portion. A serious disadvantage is that the elastic portion is connected to the chest strap part holding a fastener/adjuster ring adjacent to the fastener/adjuster ring. It is not possible to have a primarily stretching elastic portion stretching over a long section, and a channel portion for protecting it. The stretching of the elastic portion loosely surrounding the fastener/adjuster ring is strictly limited to the length determined by the sewing, which is too short a section to significantly reduce the peak forces. The fastener/adjuster ring, through which the elastic portion is threaded, due to its design, is incapable of holding the elastic portion vertically.
Therefore, the short elastic portion threaded through the fastener/adjuster ring, moving in the fastener/adjuster ring, receives load from friction as well, which does not allow prolonged use, foreshadowing the premature wearing out of the elastic portion.
The prior art development discussed above does not provide for a narrower elastic portion compared to the element limiting the stretching of the elastic portion. The elastic portion disclosed in the prior art development, having the same width as the element limiting the stretching of the elastic portion, is at least partially exposed to the harmful UV-rays of the sun, causing the premature aging of the rubber or other elastic material. Furthermore, the elastic portion of the prior art development can come into direct contact with landmarks during use, which can damage the surface of the elastic portion. A narrower design of the elastic portion than the limiting element would allow the implementation of a channel in which the length of the elastic portion could be increased. This, however, is not disclosed in the prior art. Furthermore, in the above prior art development, the design of the elastic portion and the element limiting the stretching of the elastic portion is not the same on the two sides of the chest strap, that is, on the two sides of the axis line, allowing different and predictable permanent elongation and wearing out on the two sides of the chest strap.
In the case of elastic dog harnesses found in the prior art, the components of the chest strap are not threaded through fastener/adjuster rings or frames including function-specific through openings of significantly different sizes for the individual parts of the chest strap. Therefore, the individual components of the chest strap can disadvantageously get displaced, wrinkled, and can slide down to the front legs of the dog, leading to injury or the dog getting loose. In the prior art, the use of elastic elements in dog harnesses lacks any calculation-based design with respect to wearing out, overloading, or elastic elements of widths and strengths varying as a function of the size of the dog harness.
In general, it can be stated that the prior art does not teach or suggest a dog harness in which the elastic design, the movement of the dog harness as a whole, or elements thereof, does not have an undesirable physical effect perceptible to the dog when led on a leash.